DNA, or Deoxyribonucleic Acid, and RNA, or Ribonucleic Acid, are two very similar molecules used to "code" for different traits. Some of the main differences in the two are:
A: DNA uses Deoxyribose in it's sugar-phosphate backbone, while RNA uses Ribose
B: DNA has the nitrogen base Thymine(spelling?), which is replaced with Uracil in RNA
C: DNA forms a double helix, which is pretty much a twised ladder shape, while RNA is a single helix, AKA it only has only one spiral.
D: DNA cannot leave the nucleus, while RNA can, and actually has to in order to preform its job(s).